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\begin{equation*}\int\frac{x\;dx}{(ax + b)^n} = \frac{a(1 - n)x - b}{a^2(n - 1)(n - 2)(ax + b)^{n-1}} \qquad\mbox{(for } n\not\in \{-1, -2\}\mbox{)}\end{equation*}
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